Foodborne viruses


The Swedish Food Agency is the European Union Reference Laboratory (EURL) for Foodborne Viruses and has several methods available for analysing norovirus and hepatitis A virus in the most commonly contaminated foods.

The most common cause of food poisoning is norovirus, which causes winter vomiting disease. Viruses can contaminate all types of food. One cause of such contamination is the handling of ready-to-eat foods by infected people during preparation or after heating.
Some foods may also be contaminated during production; for example, oysters, mussels or frozen imported berries.
Hepatitis A virus (HAV) is a common cause of foodborne outbreaks in Europe. In Sweden, such outbreaks are usually caused by imported frozen soft fruits.
Hepatitis E is the most common acute hepatitis disease in the world and in Europe, hepatitis E virus (HEV) is mostly transmitted from animals to people. For example, HEV may be present in meat or meat products from pigs and wild boar.

Outbreak analysis

In the event of outbreaks, the analysis of relevant food items is an important element of source tracking. The Swedish Food Agency is available to support national, regional and municipal Competent Authorities on issues such as: sampling, choice of appropriate analyses and analytical methods, evaluating results, cleaning and sanitation or with operational advice when dealing with an outbreak. The Swedish Food Agency also offers support in the form of analyses in the event of major or unusual outbreaks or when other laboratories lack the necessary methods.

To request support, please call our outbreak hotline on +46 73 354 53 23 on weekdays between 08:00 and 16:00 or the Swedish Food Agency on-call officer on +46 77 180 09 00 outside office hours. These calls go directly to the emergency operator at SOS Alarm, who will contact the on-call officer.

Accredited methods

The accredited methods used by the Swedish Food Agency to analyse foodborne viruses are listed below.

Please contact us if you would like further information and/or prices for the analyses we offer.

Martin Sandberg
Head of Unit Molecular Biology

Bivalve molluscs (oysters and mussels) Analysis method
Norovirus GI RT-qPCR
Norovirus GII RT-qPCR
Hepatitis A virus RT-qPCR


Soft fruits and leafy green vegetables Analysis method
Norovirus GI RT-qPCR*
Norovirus GII RT-qPCR*
Hepatitis A virus RT-qPCR*

*Not accredited for leafy green vegetables

Water (drinking water and raw water)  Analysis method
Norovirus GI RT-qPCR*
Norovirus GII RT-qPCR*
Hepatitis A virus RT-qPCR*

*Not accredited for water

In the event of outbreaks and other extraordinary circumstances, when requested to do so, the Swedish Food Agency may perform unaccredited analyses of other viruses and foodstuffs.

Laboratory services

Reviewed 2023-10-17